Major Stonehenge Discovery Deepens Mystery Around Ancient Monument - New findings suggest a key six-tonne stone came from over 450 miles north of the circle

Cue the conspiracy theories: new research reveals that one of Stonehenge's central and larger megaliths came neither from England, nor Wales, but from the far northeast of Scotland - and we don't know how it got there. Experts think the six-tonne altar stone must have been dragged or floated at least 750km (466 miles) south to complete the prehistoric monument.

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Cue the conspiracy theories: new research reveals that one of Stonehenge's central and larger megaliths came neither from England, nor Wales, but from the far northeast of Scotland - and we don't know how it got there. Experts think the six-tonne altar stone must have been dragged or floated at least 750km (466 miles) south to complete the prehistoric monument.

Published in the journal Nature, the new findings contradict existing beliefs that the altar stone came from Wales.

Dr Robert Ixer, honorary senior research fellow at University College London (UCL) and one of the study authors, told BBC Science Focus the discovery was "a great surprise. My first thought was disbelief."

He added: "It has an enormous significance. This Wessex-Orkney Isles connection has been known for decades, but its significance has been disputed, hotly and acrimoniously."